Samenvatting

Severe mental illness (SMI) imposes a significant burden on individuals, resulting in long-lasting symptoms, lower social functioning and impaired physical health. Physical activity (PA) interventions can improve both mental and physical health and care workers can serve as healthy role models. Yet, individuals with SMI face barriers to PA participation. This study evaluated the effects of Muva, and assessed if mental health worker’s (MHW) characteristics were associated with clients’ change in social functioning. Muva, an intervention package primarily created to increase PA of people with SMI, places a special focus on MHWs as they might play a key role in overcoming barriers. Other PA barrier-decreasing elements of Muva were a serious game app, lifestyle edu cation, and optimization of the medication regime.

Method: This study is a pragmatic stepped wedge cluster controlled trial. Controls received care as usual. Mixed effects linear regressions were performed to assess changes in the primary outcome social functioning, and
secondary outcomes quality of life, psychiatric symptoms, PA, body mass index, waist circumference, and blood pressure.

Results: 84 people with SMI were included in three intervention clusters, and 38 people with SMI in the control cluster. Compared to the control condition, there was significant clinical improvement of social functioning in
interpersonal communication (p=<0.01) and independent competence (p=<0.01) in people receiving Muva. These outcomes were not associated with MHW’s characteristics. There were no changes in the other outcome
measures.

Conclusions: Muva improved social functioning in people with SMI compared to care as usual.